This system and method are an improvement in the art of changing the glove of a glove box. A glove box is a sealed enclosure for handling radioactive, chemical, hazardous, or biohazardous material. An operator may manipulate objects inside the glove box by inserting a hand into a rubber glove that is sealed at an entrance port to the glove box.
Periodically, the gloves attached to the port must be changed. When changing the glove on a glove box port, great care must be taken to avoid box breaching. Box breaching occurs when the glove box atmosphere is allowed to escape into the room in which the box is being used. Escape of the glove box atmosphere may occur even when there is an attempt to maintain negative pressure within the box and will expose the operator and anyone near by to the hazards associated with contents of the box.
Glove changes can be accomplished by completely shutting down glove box operations and evacuating the glove box of all materials and gases. The operator may then remove the used glove and then attach a replacement glove at the operator's leisure as long as the change is complete before the glove box is put back in service.
Glove changes may be accomplished if the glove box is in service. However, this glove change method requires the operator to pull the old, used glove from the from the entrance port with one hand, while securing the new, replacement glove over the port with the other hand. The operator is often required to struggle to "muscle" the old, used glove from the port for several minutes; and during this process, the operator may briefly and unintentionally allow the new glove to come away from the port, exposing the room air to the box atmosphere. This unintentional exposure of the box atmosphere to the room is a common occurrence during difficult glove changes.
The glove changing system and method described here requires the use of at least two gloves and incorporates a primary seal (between the old, used glove and the entrance port) and a secondary seal (between the new, replacement glove and the entrance port). This system and method also incorporate the use of a disengaging means to assist in the removal of the old, used glove from the entrance port. The system and method facilitate safer, easier glove box glove changes.
Some methods for fixing a glove to a glove box have described a dual glove procedure for glove changes (see U.S. Pat. No. 4,123,123 ("'123")). The '123 patent describes a method using gloves that have an extended fin portion (i.e., longer end opposite the fingers of the glove) that folds over the port. During glove replacement, a new glove is placed on the exterior side of the old glove and a hole closing bung is inserted within the new glove to maintain a seal at the port as the old glove extended fin is released from the port. The new glove extended fin is then attached to the port and the operator completely removes the old glove by "jerking" it into the glove box.
The present system and method are an improvement over the '123 patent because the area of overlap between the old and new gloves is much smaller than the overlap of the '123 patent. No jerking action is required to remove the old glove, rather this system and method provide a mechanism to grasp and gently peel the old glove from the port of the glove box.